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1.  Consensus & Evidence-based INOSA Guidelines 2014 (First edition) 
Obstructive sleep apnoea (OSA) and obstructive sleep apnoea syndrome (OSAS) are subsets of sleep-disordered breathing. Awareness about OSA and its consequences amongst the general public as well as the majority of primary care physcians across India is poor. This necessiated the development of the INdian initiative on Obstructive sleep apnoea (INOSA) guidelines under the auspices of Department of Health Research, Ministry of Health & Family Welfare, Government of India. OSA is the occurrence of an average five or more episodes of obstructive respiratory events per hour of sleep with either sleep related symptoms or co-morbidities or ≥ 15 such episodes without any sleep related symptoms or co-morbidities. OSAS is defined as OSA associated with daytime symptoms, most often excessive sleepiness. Patients undergoing routine health check-up with snoring, daytime sleepiness, obesity, hypertension, motor vehicular accidents and high risk cases should undergo a comprehensive sleep evaluation. Medical examiners evaluating drivers, air pilots, railway drivers and heavy machinery workers should be educated about OSA and should comprehensively evaluate applicants for OSA. Those suspected to have OSA on comprehensive sleep evaluation should be referred for a sleep study. Supervised overnight polysomnography (PSG) is the “gold standard” for evaluation of OSA. Positive airway pressure (PAP) therapy is the mainstay of treatment of OSA. Oral appliances are indicated for use in patients with mild to moderate OSA who prefer oral appliances to PAP, or who do not respond to PAP or who fail treatment attempts with PAP or behavioural measures. Surgical treatment is recommended in patients who have failed or are intolerant to PAP therapy.
PMCID: PMC4248396  PMID: 25366217
Bariatric surgery; CPAP; Indian guidelines; OSA; OSAS; polysomnography; sleep apnoea; sleep study; Syndrome Z
2.  Exo70 Generates Membrane Curvature for Morphogenesis and Cell Migration 
Developmental cell  2013;26(3):266-278.
Dynamic shape changes of the plasma membrane are fundamental to many processes ranging from morphogenesis and cell migration to phagocytosis and viral propagation. Here we demonstrate that Exo70, a component of the exocyst complex, induces tubular membrane invaginations towards the lumen of synthetic vesicles in vitro and generates protrusions on the surface of cells. Biochemical analyses using Exo70 mutants and independent molecular dynamics simulations based on Exo70 structure demonstrate that Exo70 generates negative membrane curvature through an oligomerization-based mechanism. In cells, the membrane-deformation function of Exo70 is required for protrusion formation and directional cell migration. Exo70 thus represents a membrane-bending protein that may couple actin dynamics and plasma membrane remodeling for morphogenesis.
PMCID: PMC3762978  PMID: 23948253
exocyst; Exo70; actin; cell migration; membrane curvature
3.  Inverse expression states of the BRN2 and MITF transcription factors in melanoma spheres and tumour xenografts regulate the NOTCH pathway 
Oncogene  2011;30(27):3036-3048.
The use of adherent monolayer cultures have produced many insights into melanoma cell growth and differentiation, but often novel therapeutics demonstrated to act on these cells are not active in vivo. It is imperative that new methods of growing melanoma cells that reflect growth in vivo are investigated. To this end, a range of human melanoma cell lines passaged as adherent cultures or induced to form melanoma spheres (melanospheres) in stem cell media have been studied to compare cellular characteristics and protein expression. Melanoma spheres and tumours grown from cell lines as mouse xenografts had increased heterogeneity when compared to adherent cells and 3D-spheroids in agar (aggregates). Furthermore, cells within the melanoma spheres and mouse xenografts each displayed a high level of reciprocal BRN2 or MITF expression, which matched more closely the pattern seen in human melanoma tumours in situ, rather than the propensity for co-expression of these important melanocytic transcription factors seen in adherent cells and 3D-spheroids. Notably, when the levels of the BRN2 and MITF proteins were each independently repressed using siRNA treatment of adherent melanoma cells, members of the NOTCH pathway responded by decreasing or increasing expression respectively. This links BRN2 as an activator and conversely MITF as a repressor of the NOTCH pathway in melanoma cells. Loss of the BRN2-MITF axis in antisense ablated cell lines decreased melanoma sphere forming capability, cell adhesion during 3D-spheroid formation, and invasion through a collagen matrix. Combined, this evidence suggests that the melanoma sphere culture system induces subpopulations of cells that may more accurately portray the in vivo disease, than growth as adherent melanoma cells.
PMCID: PMC3591523  PMID: 21358674
cell adhesion; invasion; melanoma; metastasis; NOTCH; transcription factor
4.  Investigation into Mass Loading Sensitivity of Sezawa Wave Mode-Based Surface Acoustic Wave Sensors 
Sensors (Basel, Switzerland)  2013;13(2):2164-2175.
In this work mass loading sensitivity of a Sezawa wave mode based surface acoustic wave (SAW) device is investigated through finite element method (FEM) simulation and the prospects of these devices to function as highly sensitive SAW sensors is reported. A ZnO/Si layered SAW resonator is considered for the simulation study. Initially the occurrence of Sezawa wave mode and displacement amplitude of the Rayleigh and Sezawa wave mode is studied for lower ZnO film thickness. Further, a thin film made of an arbitrary material is coated over the ZnO surface and the resonance frequency shift caused by mass loading of the film is estimated. It was observed that Sezawa wave mode shows significant sensitivity to change in mass loading and has higher sensitivity (eight times higher) than Rayleigh wave mode for the same device configuration. Further, the mass loading sensitivity was observed to be greater for a low ZnO film thickness to wavelength ratio. Accordingly, highly sensitive SAW sensors can be developed by coating a sensing medium over a layered SAW device and operating at Sezawa mode resonance frequency. The sensitivity can be increased by tuning the ZnO film thickness to wavelength ratio.
PMCID: PMC3649373  PMID: 23389346
surface acoustic wave devices; Sezawa wave mode; mass loading effect; sensors; FEM simulation
5.  Resonant Frequency Characteristics of a SAW Device Attached to Resonating Micropillars 
Sensors (Basel, Switzerland)  2012;12(4):3789-3797.
Recently we reported experimental and simulation results on an increase in resonance frequency of a SAW resonator caused by mass loading of micropillars made of SU-8, attached normal to the surface of the resonator. We concluded that SAW resonator and the SU-8 micropillars in unison form a system of coupled resonators. We have now extended this work and performed a finite element method simulation to study the resonance frequency characteristics of the SAW-based coupled resonator. In this paper we report the effect of the resonance frequency of the micropillars on the resonance frequency of the system of coupled resonators, and observe the coupling of micropillar resonance and the propagating SAW as described in the well known Dybwad system of coupled resonators.
PMCID: PMC3355382  PMID: 22666001
surface acoustic wave devices; resonance; microsensors
Neuroscience  2010;171(4):1054-1074.
Adenylyl cyclase signaling pathways have been identified in a model hair cell preparation from the trout saccule, for which the hair cell is the only intact cell type. The use of degenerate primers targeting cDNA sequence conserved across adenylyl cyclase (AC) isoforms, and RT-PCR, coupled with cloning of amplification products, indicated expression of AC9, AC7 and AC5/6, with cloning efficiencies of 11:5:2. AC9 and AC5/6 are inhibited by Ca2+, the former in conjunction with calcineurin, and message for calcineurin has also been identified in the trout saccular hair cell layer. AC7 is independent of Ca2+. Given the lack of detection of calcium/calmodulin-activated isoforms previously suggested to mediate adenylyl cyclase activation in the absence of Gαs in mammalian cochlear hair cells, the issue of hair-cell Gαs mRNA expression was re-examined in the teleost vestibular hair cell model. Two full-length coding sequences were obtained for Gαs/olf in the vestibular type II-like hair cells of the trout saccule. Two messages for Gαi have also been detected in the hair cell layer, one with homology to Gαi1 and the second with homology to Gαi3 of higher vertebrates. Both Gαs/olf protein and Gαi1/Gαi3 protein were immunolocalized to stereocilia and to the base of the hair cell, the latter consistent with sites of efferent input. While a signaling event coupling to Gαs/olf and Gαi1/Gαi3 in the stereocilia is currently unknown, signaling with Gαs/olf, Gαi3, and AC5/6 at the base of the hair cell would be consistent with transduction pathways activated by dopaminergic efferent input. mRNA for dopamine receptors D1A4 and five forms of dopamine D2 were found to be expressed in the teleost saccular hair cell layer, representing information on vestibular hair cell expression not directly available for higher vertebrates. Dopamine D1A receptor would couple to Gαolf and activation of AC5/6. Co-expression with dopamine D2 receptor, which itself couples to Gαi3 and AC5/6, will down-modulate levels of cAMP, thus fine-tuning and gradating the hair-cell response to dopamine D1A. As predicted by the trout saccular hair cell model, evidence has been obtained for the first time that hair cells of mammalian otolithic vestibular end organs (rat/mouse saccule/utricle) express dopamine D1A and D2L receptors, and each receptor co-localizes with AC5/6, with a marked presence of all three proteins in subcuticular regions of type I vestibular hair cells. A putative efferent, presynaptic source of dopamine was identified in tyrosine hydroxylase-positive nerve fibers which passed from underlying connective tissue to the sensory epithelia, ending on type I and type II vestibular hair cells and on afferent calyces.
PMCID: PMC3025754  PMID: 20883745
saccular hair cells; dopamine D1A and D2L receptors; adenylyl cyclase isoforms 9, 7, 5/6; Gαs/olf; Gαi1; Gαi3
7.  Pharmacognostic and Phytochemical Investigation of Naringi crenulata (Roxb.) Nicols. Stem 
Ancient Science of Life  2011;31(1):17-21.
Phytochemical and pharmacognostic investigation were carried out on the stem of Naringi crenulata (Roxb.) Nicols. The pharmacognostic analysis revealed total ash of 9.65%, water soluble ash of 48.0%, alcohol soluble extractive value of 13.0% and acid insoluble ash of 48.0%. The quantitative and qualitative analysis is very essential for identifying the compounds present in the medicinal plants. The phytochemical screening revealed the presence of protein, lipid, carbohydrate, reducing sugar, phenol, tannin, flavonoid, saponin, and alkaloid, while triterpenoid, anthraquinone and quinone were absent. The present paper deals with the standardization of its aerial part of plant on the basis of various pharmacognostic parameters. The determination of these characters will aid future investigators in their pharmacological analysis of this species.
PMCID: PMC3377037  PMID: 22736885
Naringi crenulata; stem; pharmacognostical; phytochemical
9.  Molecular and Morphological Adaptations in Compressed Articular Cartilage by Polarized Light Microscopy and Fourier-Transform Infrared Imaging 
Journal of structural biology  2008;164(1):88-95.
Fifteen articular cartilage-bone specimens from one canine humeral joint were compressed in the strain range of 0% to 50%. The deformation of the extracellular matrices in cartilage was preserved and the same tissue sections were studied using polarized light microscopy (PLM) and Fourier-transform infrared imaging (FTIRI). The PLM results show that the most significant changes in the apparent zone thickness due to ‘re-organization’ of the collagen fibrils based on the birefringence occur between 0% to 20% strain values, where the increase in the superficial zone and decrease in the radial zone thicknesses are approximately linear with the applied strain. The FTIRI anisotropy results show that the two amide components with bond direction perpendicular to the external compression retain anisotropy (amide II in the superficial zone and amide I in the radial zone). In contrast, the measured anisotropy from the two amide components with bond direction parallel to the external compression change their anisotropy significantly (amide I in the superficial zone and amide II in the radial zone). Statistical analysis shows that there is an excellent correlation (r=0.98) between the relative depth of the minimum retardance in PLM and the relative depth of the Amide II anisotropic cross-over. The changes in amide anisotropies in different histological zones are explained by the strain-dependent tipping angle of the amide bonds. These depth-dependent adaptations to static loading in cartilage’s morphological structure and chemical distribution could be useful in the future studies of the early diseased cartilage.
PMCID: PMC2613829  PMID: 18634884
compression; cartilage; collagen; polarized light microscopy; Fourier-transform infrared imaging
11.  Cost of intensive care in India 
Critical care is often described as expensive care. However, standardized methodology that would enable determination and international comparisons of cost is currently lacking. This article attempts to review this important issue and develop a framework through which cost of critical care in India could be analyzed.
PMCID: PMC2738307  PMID: 19742248
Cost of critical care; cost effectiveness; cost block methodology; cost control measures
12.  Serum cholesterol level: is it a marker of sepsis? 
Critical Care  2005;9(Suppl 1):P151.
PMCID: PMC4098301
13.  Activated protein C in sepsis: an Indian experience 
Critical Care  2005;9(Suppl 1):P195.
PMCID: PMC4098345
Indian Journal of Psychiatry  1999;41(1):42-48.
225 alcoholics in village and 149 alcoholics in a mental hospital outpatients were administered screening questionnaires for alcoholics status (MAST) dependence (SADD), and consumption data (Q.F. Index). All of them underwent GGT and MCV estimation within 48 hours of last drinking. Comparison of laboratory test with the questionnaires revealed that questionnaires were more useful in community and the laboratory test in hospital where they could also be used in diagnosing monitoring and follow-up assessment of patients.
PMCID: PMC2962281  PMID: 21455352
Alcoholism; dependence; quantity-frequency (Q.F.) index; biochemical markers (GGT & MCV); sensitivity; specificity
Indian Journal of Psychiatry  1993;35(4):200-202.
A group of psychiatric outpatients who satisfied the DSM-IIIR criteria for Somatization Disorder (n=33) were compared with a group of other Somatisers (n=32). The results show that somatization disorder was found predominantly in females. Their mean age was 31 and they had a lower income and poor educational level, with more life events and stress in the family. The main symptoms were gastrointestinal, cardiopulmonary, pain and conversion followed by menstrual and sexual symptoms. They were more extroverted, neurotic and anxious depressed with significant basic neurotic traits. These results are discussed.
PMCID: PMC2980639  PMID: 21743644
16.  Molecular cloning and expression of Rhizobium fredii USDA 193 nodulation genes: extension of host range for nodulation. 
Journal of Bacteriology  1986;168(3):1087-1095.
DNA hybridization with the cloned nodulation region of Rhizobium meliloti as a probe revealed DNA homology with four HindIII fragments, 12.5, 6.8, 5.2, and 0.3 kilobases (kb) in size, of the symbiotic plasmid pRjaUSDA193. Both hybridization and complementation studies suggest that the common nodulation genes nodABC and nodD of R. fredii USDA 193 are present on the 5.2-kb HindIII and 2.8-kb EcoRI fragments, respectively, of the Sym plasmid. Both fragments together could confer nodulation ability on soybeans when present in Sym plasmid-cured (Sym-) and wild-type (Sym+) Rhizobium strains or in a Ti plasmid-cured Agrobacterium tumefaciens strain. Furthermore, the 2.8-kb EcoRI fragment alone was able to form nodulelike structures on Glycine max L. cv. "Peking" (soybean). Microscopic examination of these nodules revealed bacterial invasion of the cells, probably via root hair penetration. Bacterial strains harboring plasmids carrying the 5.2- and 2.8-kb nod fragments elicited root-hair-curling responses on infection. These data suggest that the genes responsible for host range determination and some of the early events of nodulation may be coded for by the 5.2-kb HindIII and 2.8-kb EcoRI fragments.
PMCID: PMC213606  PMID: 3782034
Indian Journal of Psychiatry  1984;26(4):390-392.
Sexual behaviour in forty mile schizophrenics on maintenance medication were studied. Authors observed that thirteen patients reported decrease in frequency of sexual thoughts, fifteen in frequency of intercourse. Eight patients reported decline in enjoyment of intercourse and six avoided sex.
PMCID: PMC3011205  PMID: 21966018

Results 1-17 (17)